Compressed-air brake for trolley cars, railway cars, trains, and other vehicles



jm, 20 i925. 1,523,913

S. SYMINGTON coMPREssED AIR BRAKE EOE TROLLEY cms, RAILWAY GARS, TRAINS, AND OTHER VEHICLES Filed July s. 1924 Patented Jan. 20, 1925.

UNITED STATES SCOTT SYMINGTON, OF STROUDSBURG, PENNSYLVANIA.

COMPRESSED-AIR BRAKE FOR TROLLEY GARS, RAILWAY CARS, TRAINS, AND OTHER VEHICLES.

To all whom it may concern.'

Be it known that l, SCOTT SYMrNGToN, a subject of the King of England, residing at 515 Thomas Street, Stroudsburg, in the county of Monroe andState of Pennsylvania. have invented a new and useful Improvenient in Connection with Compressed- Air Brakes for Trolley Cars, Railway Cars, Trains, and Other Vehicles.

The objects of the improvement are twofold. (l) the attainment ot economy in the consun'iption of air and power (2) the provision ot means whereby the brakes may be applied gradually with greater facility than by methods ot operation used hitherto.

The general method of operation of air brakes in use hitherto is as follows:- Atmospheric air is pumped into a receiving or storage chamber by an air compressor to a pressure ot approximately 8O pounds per square inch.

lVhen an application of the brakes is desii-ed, a quantity of this compressed air is admitted into a cylinder containing a piston by means ot' a valve. Motion is thus imparted to the piston which is transmitted to the brake-shoes or brake-bands by a system ot rods or rods and chains and multiplying levers.

The brakes are released by allowing the air in the cylinder containing the moveable piston to escape to the atmosphere, the return of the piston to the off position being accomplished by means of springs.

My invention is designed to eti-'ect econonly by saving a portion of the air under compression ordinarily exhausted to atmosphere by providing one or more auxiliary storage chambers into which the used compressed air is expanded in successive order until it reaches a pressure at which no `further practical economy can be obtained and the balance is allowed to escape to the atmosphere. The compressed air thus stored is used in successive applications of the brakes.

Then a series of reservoirs is used, the pressure in the first reservoir will always be higher than that in the second, and that in the second higher than that in the third and so on throughout the series.

In practice probably not more than two auxiliary reservoirs would be used with advantage.

In the drawing forming part ot' this Application filed July 5, 1924.' Serial No. 724,423.

specification, Figure l is a diagrammatic plan illustrative of a complete air brake system with my invention incorporated.

Figure Q is an elevation of a combination inotormans operating valve and auxiliary reservoir.

Figure 3 is vertical section of this combined operating valve and reservoir.

Figure `Il is an enlarged horizontal section through the valve showing all the ports and in the position in which air passes from the main reservoir to the brake cylinder.

Figure 5 is an enlarged horizontal section through the valve in the position in which air passes from the brake cylinder to the auxiliary reservoir or vice versa.

Figure 6 is an enlarged horizontal section through the valve in the position in which air passes from the brake cylinder to the atmosphere.

The method of operation is illustrated in diagrammatic form in Fig. l.

For the purpose of illustration the diagram shows a. very simple form of brake transmission but the invention is equally applicable to brake systems with multiple lever and rod systems.

It also shows only one auxiliary reservoir. Additional reservoirs can readily be added each reservoir requiring its own outlet and inlet port or valve.

A valve of the slide type is indicated for ease in illustration but the invention is not confined to any particular type of valve.

Valves of the piston or rotating types may be used or if expedient a series ot' vtappet valves could be arranged.

It is the belief ot the inventor that a valve in the form ot a multiple way plug cock will be the cheapest and most suitable.

Referring to Fig. l the operation is as itollows Air is compressed by the compressor il into the storage chamber 2.

In making an application of' the brakes the valve 8 is moved till the port et is opposite the port 5 and a quantity of conn pressed air from the chamber 2 is admitted to the valve chamber 6, passes along the pipe 7 to the cylinder 8 and pushes the piston 9, the motion ot which is transmitted by brake rigging 10 to the friction shoe 1l.

When sutlicient air has been admitted to stop or retard the motion ofV the vehicle as desired, the valve 3 is moved to a point in which the port et is midway between port 5 and port 1Q and is closed. The air in cylinder 8 is held in compression. When it is desired to release the brakes the valve fl is moved turther in the same direction till port 4 is directly opposite port 12 and the air in the cylinder S is released and expanded into the auxiliary reservoir 1B until the pressure in both is equal and a point of equilibrium is reached. The motion of the valve 3 is Vfurther continued till the port 4 is opposite port 14: and the balance o't' the air in the brake cylinder 8 is released to atmosphere through the pipe l5 and the brakes are thus fully released. The air under compression in auxiliary reservoir 13 is stored by the closing o'l': thc port 12. On the next application of the brakes the action is reversed. When the port l is again brought opposite port 12.. the compressed air in reservoir 13 re-expands into cylinder 8 causing a partial or low Ypressure application ot the brakes. Full Vapplication is then made it' desired by further motion ot valve 3, allowingdirect communication between the reservoir 2 and the cylinder S. This ends one complete cycle ot operations.

It is obvious that the pressure in auxiliary reservoir 18 Will build up with each successive release of the brakes until a maximum point is reached. This maximum can never reach the maximum pressure in the storage reservoir 2. lt may be found expedient to limit the pressure inauxiliary reservoir 13, which result may be readily attained by pressure relierl valve. Multiple auxiliary receivers if added to the system must each be connected to aditional separate ports in the valve face 16.

A moreV practical design of the apparatus is shown on Figs. 2, 3, 4.-, 5, 6, this form consisting of a combination opera-ting valve and auxiliary receiver but itis notlthe desire ot the inventor to conne this application in any Way to this type or combination.V This design is merely given to show the practicability and simplicity ot the invention. lt is desired to point ont that the systems ot operation in use hitherto can very readily be changed to the system covered by this invention by substituting the apparatus shown on Figs. 2, 3, et, 5, G for the present types of operators valves and some minor piping alterations. Y

The type shown in Figs. 2, 3, 4, 5, 6 makes use of aV multiple way plug` cock 17 With a vertical axis set vertically above one auxiliary reservoir which at the same time forms a stand or base for the plug cock type operating valve and is intended to be bolted to the operating platform of the vehicle. The design shown is provided with a spring 28 and a ball bearing 29 to assist the rotating operation.

ln explanation oi' the design the central opening 19 ot the valve 1T is directly conne led to the brake cylinder by the pipe 20. The pipe 21 is connected to the primary source ot' compressed air. The pipe 2T leads to the atmosphere and the passage 25 leads to the auxiliary reservoir 1S.

The ports in the valve seat and the 'valvc 1T are each three in number and are distributed round the peripheries of the valve and scat. Two of these ports 22, 23 are shown on the vertical cross section. Fig. il and, ports Q2, L3. iat are shown on the horizontal cross sections l, 5. G.

lfort 2'2 is the auxiliary reservoir port. Porti Ql is the primary nir supply port and port 2l is the exhaust port. It: will be seen that the rotation of the valve li by tho operating handle 26 permits the connecting ot the bralse cylinder, through the central opening ot the valve. in turn to the i'niniary source ot air supply, the auxiliary reservoir and the atmosphere. The operation ol' the valve is thc same as the operation previously described for Fig. l. It is desired to point out that a neutral or closed position must be provided between each open position.

l claim:

l. ln apparatus for stopping the motion ot moving vehicles, the combination ot a means for providing a supply oll compressed air, means for admitting compressed nir as desired into a cylinder containingl .1 piston, :i cylinder containing a piston` means tor '.ransmitting pressure on the piston to friction surt'accs arranged so :1s to stop the rotation oit the wheels ot thc vchirlc, means for allowing` compressed air to pass` from the cylinder to a storage reservoir; and 'trom the storage reservoir to thc cylinder :is desired, a storage reservoir arranged to store part ol" the compressed air when allowed to escape from the cylinder and mcans for allowingv compressed nir to escape from the cylinder to the atmosphere as desired.

2. ln apparatus tor stopping the motion of moving Vehicles, the combination ot! a means for providing a supply ot compressed air` means for admitting compressed air as desired into n cylinder containinga piston. a cylinder containing a. piston. means for transmitting prcssiire on the piston to friction surfaces arranged so as to stop the rotation ot the wheels oi'V the vehicle. means for allowing compressed air to pass trom the Acylinder to a storage reservoir and from the storage reservoir to the cylimlcr as desired, a storage reservoir arranged to store part of the compressed air when allowed to escape from the cylinder. means for limiting the pressure of the compressed air in the storage reservoir` and means for allowing compressed air to escape from the cylinder to the atmosphere as desired.

3. ln apparatus for stopping the motion lll) o't moving vehicles, tlie combination oit a means 'for providing a supply of compressed air, means tor admitting compressed air as desired into cylinders eacli containing a piston, cylinders eacli containing a piston, ineans for transmitting pressure on the pistons to friction surfaces arranged so as to stop tlie rotation ot the wheels of the vehicle, means `for allowing compressed air to pass from the cylinders to a storage reservoir and Vtrom tlie storage reservoir to the cylinders as desired., a storage reservoir arranged to store part of the compressed air when allowed to escape from the cylinder, and means for allowing compressed air to escape trom tlie cylinders to tlie atmosphere as desired.

Ll. In apparatus for stopping tlie motion of .moving vehicles, the combination ot a means for providing a supply of compressed air, means tor admitting compressed air as desired into cylinders each containing a piston, cylinders eacli containing` a piston, means tor transmitting` pressure on the pistons to friction surfaces arranged so as to stop tbe rotation ot tlie wheels ot tlie veliicle. means for allowing` compressed air to pass trom tlie cylinders to a storage reservoir and 'from the storage reservoir to tlie cylinders as desired,a storage reservoir arranged to store part of tlie compressed air when allowed to escape from tlie cylinders, means tor limiting the pressure of tlie compressed air in the storage reservoir, and ineens for allowing compressed air to escape Atrom tbe cylinders to tlie atmosphere as desired.

5. In apparatus for stopping the motion et moving vehicles, tlie combination of a means torproviding a supply of compressed air. means for admitting compressed air as desired into a cylinder containing a piston, a cylinder containing a piston, means for transferring pressure on tlie piston to friction surfaces arranged so as to stop the rotation ot the wheels of the veliicle, means tor allowing compressed air to pass from tlie cylinder to a succession o storage reservoirs and Afrom tbe succession of storage reservoirs to the cylinder as desired, a succession ot storage rese-rifoirs arranged to store part of tbe compressed air when allowed to escape from tlic cylinder, and means vfor allowing compressed air to escape trom tbe cylinder to the atmosphere as desired.

t3. In apparatus for stopping the motion ot' moving vehicles, the combination of a means for providing' a supply of compressed air` means for admitting compressed air as desired into a cylinder containing a piston, a cylinder containing a piston, means tor transferring pressure on the piston to friction surfaces arranged so as to stop the rotation ot the wheels of tlie vehicle, means for allowing compressed air to pass from tlie cylinder to a succession of storage reservoirs and trom the succession of storage reservoirs to the cylinder as desired, a succession of .storage reservoirs arranged to store part ot' the compressed air when allowed to escape 'troni the cylinder, means for limiting tlic pressure ot' the compressed air in the storage reservoirs, and means for allowing compressed air to escape from tlie cylinder to tlie atmosphere as desired.

.7. In apparatus for stopping the motion ol moving vehicles, the combination ot a n'ieans 'tor providing a supply of compressed air, means for admitting compressed air as desired into cylinders each containing a piston, cylinders eacli containing a piston, means for transmitting pressure on the pistons to friction surfaces arranged so as to stop tlie rotation oit the wheels of the vehicle, means for allowing compressed air to pass trom tlie cylinders to a succession of storage reservoirs and from the succession ot storage reservoirs to the cylinders as desired, a succession of storage reservoirs arranged to store part of the compressed air when allowed to escape from the cylinders and means 'for allowing compressed air to escape from the cylinders to the atmosphere as desired.

S. In apparatus lor stopping the motion of moving vehicles, the combination of a means 'for providing a supply of compressed air, means for admitting compressed air as desired into cylinders each containing a piston, cylinders eacli containing a piston` means for transmitting pressure on tbe pistons to friction surfaces arranged so as to stop the rotation of tbe wheels of tlie vehicle. means tor allowing compressed air to pass from the cylinders to a succession ot storage reservoirs and from tbe succession ot storage reservoirs to tbe cylinders as desired, a succession of storage reservoirs arranged to store part of tlie compressed air when allowed to escape from tlie cylinders, means for limiting` the pressure of the compressed air in the storage reservoirs, and means for allowing compressed air to escape from tbe cylinders to tlie atmosphere as desired.

SCOTT SYMINGTON 

